Potentiometer adjuster



Jan. 3, 1961 c. L. GARVER ET AL 2,966,807

POTENTIOMETER ADJUSTER Filed April 21, 1958 2 Sheets-5heet 1 FIG. 2 JNVENTORS.

CLYDE GARVER GERALD L. KRING BY BASSETT B. NYE

Jan. 3, 1961 vc. L. GARVER ET AL 2,966,807

POTENTIOMETER ADJUSTER Filed April 21, 1958 2 Sheets-Sheet 2 INVENTORS. CLYDE L. GARVER GERALD L. KRING BY BASSETT B. NYE

United States Patent POTENTIOMETER ADJUSTER Clyde L. Garver, Grand Rapids, Gerald L. Kring, Grandville, and Bassett B. Nye, Grand Rapids, Mich., assignors to Lear, Incorporated Filed Apr. 21, 1958, Ser. No. 729,960

4 Claims. (Cl. 74-504) This invention relates to improvements in rotatable controls such as those employed in instrument panels to adjust the setting of a potentiometer, variable condenser or other adjustable apparatus.

It is desirable to have a control switch which operates one or more switches, adjusts a potentiometer or other adjustable apparatus and returns to zero or null position re-establishing one or more circuits after an adjustment has been made. It is also desirable to protect this control knob against accidental disturbances. In the past, the control knobs or switches have been placed in recesses in the panel or have been covered to avoid accidental disturbances. Also, manual operation was required to return the control knobs to the zero or null position. By protecting the control knob from accidental disturbances, the control knob is placed in a position which makes access somewhat difiicult and manual return to zero or null position of the control knob leaves an opportunity for error.

Therefore, it is an object of this invention to provide a control switch which is easily accessible and yet prevents inadvertent movement.

It is another object of this invention to provide a control switch which will automatically return to the angular zero or null position from either a clockwise or counterclockwise setting.

Other objects and a fuller understanding of the invention will become apparent from the following description when taken in conjunction with the drawings in which:

Fig. 1 is a top view of the present invention;

Fig. 2 is a cross-sectional view taken along line 2-2 of Fig. 1;

Fig. 3 is a cross-sectional view taken along line 3-3 of Fig. l; and

Fig. 4 is a side view of the present invention.

Referring now to the drawings, there is shown in Fig. 2 a support having screw threads on one end thereof. A potentiometer 11 has screw threads thereon and is capable of being threaded into the support 10 and locked there by the locking nut 12. The shaft 13 protrudes through support 10 such that the rotation axis of shaft 13 is in line with the rotation axis of the tuning screw 14 of potentiometer 11 and the shaft 13 protrudes into a slot in the tuning screw 14. The shaft 13 has pins 15 and 16 attached to and extending from the flange on shaft 13. The pins 15 and 16 extend into the holes 17 and 18 in the support 10.

A coil spring 19 abuts one end of the support 10 and the collar 20, which surrounds a portion of shaft 13, contacts the other end of spring 19. It is to be noted that the shaft 13 is capable of rotating relative to the collar 20. A metal ring 21 rests against the shoulder 22 of shaft 13 and is separated from the collar 20 by bearing 23. The ring 21 is urged against the shoulder 22 of shaft 13 by the spring 19.

A second spring 24 is positioned about the circumference of shaft 13 and has its ends 25 and 26 extending out on opposite sides of the shaft 13 and over the support 10. A second set of pins 27 and 28 attached to the shaft 13 are positioned such that rotation movement of the shaft 13, in either a clockwise or counter-clockwise movement, will cause one of the pins 27 or 28 to push against one end of the spring 24 and effect a torque to be exerted upon the shaft 13. A third set of pins 29 and 30 extend from the collar 20 so that when the shaft 13 is moved longitudinally, the longitudinal force in one direction against the spring 19 is transmitted from shaft 13 through the ring 21 and bearing 23 causing the collar 20 and pins 29 and 30 to also move longitudinally. Rotation of shaft 13 does not cause any rotation of collar 20. Micro switches 31 and 32 are positioned to be actuated by the longitudinal movement of pins 29 and 30. The spring 19 urges the collar 20, shaft 13 and pins 29 and 30 back to a neutral position when the force on shaft 13 is released. The shaft 13 also has on one end thereof a control knob 33. The support 10 is adapted to fit in a hole in panel 34 and be held there by a nut 35.

As shown in the drawings, the control switch is in a locked position; the pins 15 and 16 are in the holes 17 and 18 and thereby restrict rotational movement of the shaft 13. If, however, a force is applied to the shaft 13 sufi'icient to overcome the urging of spring 19 along the longitudinal axis, the shaft will move linearly until its shoulder 36 comes in contact with the end 37 of potentiometer 11. Once in this position, the pins 15 and 16 are out of the holes 17 and 18 and hence, the shaft 13 may rotate if torque is applied. If the shaft is turned, for example, in a clockwise direction, it can be seen then that the pin 28 will pick up the end 26 of spring 24 thereby forcing the other end 25 of spring 24 against the support 10. The spring 24 causes a torque to be exerted upon the shaft 13. When the torquing force applied to the shaft 13 at the control knob 33 is released, the spring 24 urges the shaft back to a neutral or null angular position and the spring 19 urges the shaft 13in a longitudinal direction causing the pins 15 and 16 to re-enter the holes 17 and 18 and thereby lock the shaft 13 in its neutral or null position.

It is to be noted that the sample use of this switch has been with a potentiometer and in this example it is desirable to actuate two switches prior to changing the setting of the potentiometer 11. This is accomplished by the pins 29 and 30 extending from the collar 20 such that when the shaft 13 moves into a position whereby the pins 15 and 16 are not restricting rotation of shaft 13, the switches 31 and 32 are actuated by the pins 29 and 30 and when the shaft 13 returns to its neutral position, the switches 31 and 32 are also allowed to return to their original position.

Although the present invention has been described with a certain degree of particularity, it is understood that various modifications in the details and arrangements of parts may be had without departing from the spirit and scope of the invention as hereinafter claimed:

We claim:

1. A control device comprising a support, a shaft mounted on said support having linear and angular freedom relative to said support, means for prohibiting rotation of said shaft in a first linear position, first resilient means for urging said shaft into said first linear position, and second resilient means for urging said shaft into a first neutral rotary position from which said shaft is capable of being temporarily urged by sufiicient force to overcome both of said resilient means and disengage said prohibiting means into a position other than said first linear and rotary positions.

2. A control device comprising a support, a shaft mounted on said support having linear and angular freedom relative to said support, said shaft having pins thereon for engaging said support and restricting rotation of said shaft when said shaft is in a first linear position, first Patented Jan. 3, 1961 spring; means for urging said shaft into said first linear position and second spring means for urging said shaft into a first neutral rotary position from which said shaft is capable of being temporarily urged by sufficient force to overcome both said resilient means and disengage said restricting means into a position other than said first linear and rotary positions.

3. A control device comprising a support, a shaft mounted on said support having linear and angular freedom relative to said support, said shaft having first pins thereon for engaging said support and restricting rotation of said shaft when said shaft is in a first linear position, first spring means for urging said shaft into said first linear position, and a second spring means having the ends of said second spring extending over said support and a second set of pins on said shaft such that when said shaft is rotated at least one of said second pins is positioned to pick up one end of said second spring while the other end of said second spring is held against said support causing a torque to be exerted on said shaft in the opposite direction of rotation of said shaft, said shaft being capable of 4. being temporarily'urged. by sufficient force to overcome both of said spring means and disengaging said first pins into a position other than said first linear and neutral rotary positions. 5

4. The device as claimed in claim 3 wherein said shaft has provisions associated therewith for actuating a switch when said shaft is moved linearly to and from said first linear position.

References Cited in the file of this patent UNITED STATES PATENTS 2,316,626 Rothwell Apr. 13, 1943 2,496,880 Leland Feb. 7, 1950 2,631,203 Mehilburg Mar. 10, 1953 2,716,874 Wilby Sept. 6, 1955 2,752,513 Boyd June 26, 1956 2,762,876 Glogan et a1 Sept. 11, 1956 2,812,453 Mastney Nov. 7, 1957 2,813,182 Van Alen Nov. 12, 1957 2,881,621 Prindergast et al. Apr. 14, 1959 

